Service parts for the MDJA
Grouped by system, with how many of each the parts manual calls for.
Air intake
1 requiredFuel system
1 requiredOil system
1 requiredBelts
1 requiredPrices captured from merchant listings; some links are affiliate links. Confirm against your serial number before ordering.
Specifications
| Fuel | diesel |
|---|---|
| Frequency | 60.0 Hz |
| Standby power | 3 kW |
| Standby kVA | 3 |
| Controller | Analog control panel: battery charge rate ammeter, preheat switch, start-stop switch, field circuit breaker |
| Oil capacity | 2.4 L |
| Voltage options | 120 V, 240 V, 120/240 V |
| Phase | 1 |
| Power factor | 1.0 |
| Battery group | 1H |
| Battery cranking | 450 CCA |
| Battery voltage | 12 V |
| Battery quantity | 2 |
| Dimensions (L×W×H) | 727×524×681 mm |
| Dry weight | 166 kg |
Engine
| Oil capacity | 2.5 L |
|---|---|
| Coolant capacity | 4.0 L |
| Displacement | 0.5 L |
| Aspiration | natural |
| Rated speed | 1800 rpm |
Maintenance & consumables
for the Cummins/Onan MDJA| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | Breather Filter Element | 123-1871 | Amazon eBay | ||
| Fuel filter | Fuel Filter Element | 149-0428 | Amazon eBay | ||
| Fuel filter | Secondary | — | 3000 hr | ||
| Oil filter | Oil Filter | 122-0185 | Amazon $8.99 Amazon eBay $19.55 eBay | ||
| Battery | — | 100 hr | |||
| Belt | Water Pump Belt Heat Exchanger Pump | 511-0067 | Amazon eBay | ||
| Coolant | Optional heat-exchanger (captive water) cooling system capacity; 50/50 ethylene glycol/water mix recommended | — | |||
| Oil | API CD/SE or CC/SE | — | 100 hr |
Common questions
What is the power rating of the Cummins/Onan MDJA?
The Cummins/Onan MDJA is rated 3 kW standby (3.0 kVA).
Which engine powers the Cummins/Onan MDJA?
The Cummins/Onan MDJA is powered by the Cummins/Onan MDJA engine.
Is the Cummins/Onan MDJA diesel or gas?
The Cummins/Onan MDJA runs on diesel.
What's the oil capacity on a Cummins/Onan MDJA?
The Cummins/Onan MDJA engine in the Cummins/Onan MDJA has an oil capacity of 2.5 liters.
What oil filter does the Cummins/Onan MDJA use?
The Cummins/Onan MDJA uses oil filter part number 122-0185.
What fuel filter fits the Cummins/Onan MDJA?
The Cummins/Onan MDJA uses fuel filter part number 149-0428.
Which air filter part number does the Cummins/Onan MDJA take?
The Cummins/Onan MDJA uses air filter part number 123-1871.
Troubleshooting
1Symptoms & remedies
| Symptom | Remedy |
|---|---|
| Do not work on energized equipment | Do not work on energized equipment. Unauthorized personnel must not be permitted near energized equipment. Induced voltage remains even after equipment is disconnected from the power source. Plan maintenance with authorized personnel so equipment can be de-energized and safely grounded. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Repair guides
1Step-by-step procedures compiled from the Cummins/Onan service manual for this model.
Parts
13| Part # | Description | Qty | System | |
|---|---|---|---|---|
| 122-0185 | Oil Filter | 1 | Oil filter | Amazon $8.99 Amazon eBay $19.55 eBay |
| 122-0325 | PRIMARY Fuel Filter Element | 1 | Fuel filter | Amazon eBay $75.00 |
| 122-0326 | SECONDARY Fuel Filter Element | 1 | Fuel filter | Amazon eBay $65.00 |
| 123-1871 | Breather Filter Element | 1 | Air filter | Amazon eBay |
| 132-0110 | Fresh Water Pump - With Metal Impeller | 1 | Pump | Amazon eBay |
| 132-0133 | Fresh Water Pump - With Keel Cooler Kit | Pump | Amazon eBay | |
| 149-0428 | Fuel Filter Element | 1 | Fuel filter | Amazon eBay |
| 309-0156 | High Temperature Cutoff Switch | 1 | Switch | Amazon eBay |
| 333-0106 | Glow Plug (12 Volt) | 2 | Glow plug | Amazon eBay |
| 511-0067 | Water Pump Belt Heat Exchanger Pump | 1 | Belt | Amazon eBay |
| 130-1340 | Zinc Pencil | 1 | Service part / kit | Amazon eBay |
| 155-0950 | Siphon Break Kit (prevents sea water siphoning into engine when exhaust injection elbow is below load waterline) | 1 | Service part / kit | Amazon eBay $85.00 |
| 308-0155 | Part 308-0155 | 1 | Service part / kit | Amazon eBay |
Service, wear & replacement parts referenced for this model and its engine — confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.